Bitcoin coins are seen in this file photo. Trading volumes at China’s three largest bitcoin exchanges have plummeted after the central bank put the virtual currency market under sharper scrutiny a month ago.© Benoit Tessier / Reuters/Reuters Jacob Silverman is a journalist in New York. He is the author of two books and the host of the new CBC podcast on the fall of cryptocurrency exchange FTX, The Naked Emperor. As a slow-motion banking crisis rippled through markets in recent weeks, something strange happened: Crypto prices rallied, with Bitcoin rising from a low of about US$20,000 to about US$28,700 in...